People have maintained a steady presence in area on the Worldwide Area Station (ISS) for greater than 20 years now. It’s our longest-running and most complete experiment in long-duration spaceflight. However the ISS is frequently equipped with consumables – meals, water, and oxygen – so astronauts are largely reliant on Earth. If Humanity is ever going to stay and work in area long run, we’re going to need to be taught to be extra self-reliant – and which means rising meals in area.
With this in thoughts, the NASA Glenn Plant Water Management (PWM) project has been diligently learning one of the simplest ways to supply water and aeration to crops rising on the ISS. Earlier experiments have confirmed that crops can develop in area, however the circumstances of microgravity usually are not splendid.
There’s some proof that area makes crops extra susceptible to contamination by microbes. A crop of zinnias grown on the ISS in 2015 was partially killed off by fungus. A little bit tender loving care from astronaut Scott Kelly was capable of save just a few of the crops, who nursed the remaining zinnias again to well being.
One other vital problem for gardening in microgravity is that crops’ root programs behave otherwise than on Earth, creating sudden challenges in delivering water to the crops. It’s this downside that the PWM mission hopes to sort out.
There are two widespread methods to ship water to the roots. The primary, like most agriculture on Earth, is to ship it by an middleman: soil. A second choice, often known as hydroponics, entails rising the crops straight in water.
To check the effectiveness of those strategies, the PWM group delivered synthetic crops to the area station. These foam, felt, and sponge creations simulated the foundation programs and the evaporation charge of an actual plant (which they didn’t use largely to extend the experiment’s shelf life). The simulated crops had been ‘watered’ with fruit punch reasonably than water, making it simpler to see the liquid being absorbed, and to supply the ‘crops’ with helpful vitamins and sugars.
One of many key necessities of the mission was that the water supply system wanted to be efficient throughout the plant’s whole life cycle, from seed to leaf. If a plant dies in germination (or anytime after), it might probably’t be harvested, so researchers wanted to account for each life stage.
The PWM mission wrapped up its experiments on the ISS in early April. The outcomes are nonetheless pending, however the group plans to run additional experiments sooner or later to additional refine their rising methods.
The PWM mission is simply the newest in an extended historical past of plant science in area. The primary plant ever totally grown in orbit was an Arabidopsis – a plant associated to cabbage and mustard – aboard the Soviet area station Salyut-7 in 1982 (An earlier Soviet experiment managed to germinate seeds in area in 1966).
Since then, quite a lot of totally different crops have been grown on the ISS, together with lettuce, Swiss chard, radishes, Chinese language cabbage, peas, sunflowers, and the aforementioned zinnias. A few of these are used for analysis, and the remaining go straight into the astronauts’ lunch.
Study Extra: Adam Schabel, “Project Examines How to Water Plants in Space.” NASA Glenn.
Featured Picture: a zinnia on the ISS, with Earth within the background. Credit score: NASA.